Telephone network interface devices (“NIDs”) provide a demarcation, or interface, between external telephone company lines and a subscriber's internal wiring. The NID contains a number of smaller components, typically line modules or protected termination devices (“PTDs”), within which telephone company and subscriber tip and ring wiring is physically interconnected. Each PTD contains a jack and subscriber terminals to which tip and ring wires are secured. There is also a hinged cover that protects the internal components. The cover includes a plug that is seated inside the jack when the cover is closed. Opening the cover removes the plug from the jack to allow a telephone handset to be connected to the telephone company wiring for testing.
An important operational aspect of PTD design is to enable the telephone company to test the wiring connections established by the PTD. Conventional PTDs dispose access holes referred to as test ports through rear portions of the cover at locations that are proximate the subscriber terminals. The test ports permit probes to be inserted through the cover and contact the terminals to verify telephone service to the NID. The test ports permit this testing to be done while the cover remained closed. An example of this arrangement is described in U.S. Pat. No. 5,548,641 issued to Butler et al., which is owned by the assignee of the present invention and is incorporated herein by reference in its entirety.
While the conventional test port arrangement affords an effective and reliable technique for testing wiring connections, an alternative arrangement is desired. Screw-type terminals, such as those depicted in U.S. Pat. No. 5,548,641, are being largely replaced in newer PTDs with insulation displacement connectors (“IDCs”) to which the subscriber tip and ring wires are connected. In a particular design, the IDCs employ lever switches to connect and disconnect the wiring. Viewing windows are placed in the cover over each of the switches so that the position of the lever can be easily seen without opening the cover. In addition, labeling is placed on the cover that indicates the lever is in either a connected or disconnected state. The presence of the windows and the labeling on the cover leaves insufficient room for test ports to be disposed through the cover.
The present invention addresses this problem presented by the use of PTDs provided with lever activated IDCs.